Given the highly non-Gaussian nature of the process of reionization [1]}, [2]}, [3]}, [4]}, one would need to employ statistical tools which encapsulate information of higher order correlations. For a Gaussian random field the power spectrum contains all the spatial information and no new information is obtained from higher order correlations. Therefore, to probe the EoR one needs to resort to higher order Fourier statistics of the 21cm brightness temperature, such as the bispectrum [5]}, [6]}, [7]}, [8]}, [9]} or use the phase space statistics [10]} to infer non-gaussian features of the 21cm signal.
